x402-crosschain-gas
GET https://x402-catalog-history.ai-business-surface.workers.dev/gas
Listed in PayAI
Stop opening five explorers to price one transaction: one GET returns what each chain is charging for gas right now — for base, eth, arbitrum, optimism and polygon: the current gas price in gwei (with the raw wei the RPC returned), the latest block's base fee, the priority fee a 50th-percentile transaction actually paid across the last five blocks, the next block's base fee under the EIP-1559 formula, the block number and timestamp those numbers came from, and the public RPC that answered. curl: GET /gas?chains=base,eth (omit chains for all five; aliases like ethereum or arb work). Response: {gas:[{chain,chain_id,gas_price_gwei,base_fee_gwei,priority_fee_gwei,block:{number,timestamp},source_rpc,fetched_at}]}. Every value is a measurement from a public RPC, never an estimate: a chain no RPC answered for is listed in chains_unavailable with the reason, and a figure that could not be measured is null. Values are cached for 15 seconds, and each one carries the fetched_at of the measurement
How to buy
This endpoint takes pay-per-call payments over x402. Call it once without paying to see its live price; any x402 client then pays and retries automatically.
curl -i -X GET "https://x402-catalog-history.ai-business-surface.workers.dev/gas"
# HTTP/1.1 402 Payment Required: price, asset and payTo are in the responseRecent checks
| Checked (UTC) | Result | Status | Time | Live price |
|---|---|---|---|---|
| 2026-10-14 06:15 | Valid 402 | 402 | 119 ms | $0.001 |
Receipts
No test purchases yet. Graded test purchases are next on our list; until then every number here comes from unpaid checks.
What a check proves